Mechanisms for the Breakdown of Halomethanes through Reactions with Ground-State Cyano Radicals
2015 (English)In: ChemPhysChem, ISSN 1439-4235, E-ISSN 1439-7641, Vol. 16, no 1, 181-190 p.Article in journal (Refereed) Published
One route to break down halomethanes is through reactions with radical species. The capability of the artificial force-induced reaction algorithm to efficiently explore a large number of radical reaction pathways has been illustrated for reactions between haloalkanes (CX3Y; X=H, F; Y=Cl, Br) and ground-state (2Σ+) cyano radicals (CN). For CH3Cl+CN, 71 stationary points in eight different pathways have been located and, in agreement with experiment, the highest rate constant (108 s−1 M−1 at 298 K) is obtained for hydrogen abstraction. For CH3Br, the rate constants for hydrogen and halogen abstraction are similar (109 s−1 M−1), whereas replacing hydrogen with fluorine eliminates the hydrogen-abstraction route and decreases the rate constants for halogen abstraction by 2–3 orders of magnitude. The detailed mapping of stationary points allows accurate calculations of product distributions, and the encouraging rate constants should motivate future studies with other radicals.
Place, publisher, year, edition, pages
2015. Vol. 16, no 1, 181-190 p.
gas-phase reactions; quantum chemistry; radical reactions; reaction mechanisms; transition states
IdentifiersURN: urn:nbn:se:uu:diva-228448DOI: 10.1002/cphc.201402601ISI: 000347239200018PubMedID: 25263486OAI: oai:DiVA.org:uu-228448DiVA: diva2:734148
FunderMarcus and Amalia Wallenberg FoundationSwedish Research CouncilSwedish National Infrastructure for Computing (SNIC), p2011004